#include<stdio.h>
#pragma warning(disable:4996)
int main()
{
	int sum = 0;
	int n = 0;
	scanf("%d", &n);
	int i = 1;

	for (i = 1; i <= n; i++)
	{
		 sum += i;
		 printf("sum=%d\n", sum);
	}
	printf("sum=%d", sum);
	return 0;
}